Обзор решений

CO2 emission certificates: The precise CO2 direct measurement by SICK is a reliable alternative to the complex mathematical method.

Task

It is nothing new: the economy can also contribute to climate protection. In the Kyoto protocol, the industrial nations agreed on a limit for greenhouse gas emissions. The greenhouse gas CO2 is one of six gases which have to be reduced worldwide. The directive 2003/87/EC for trading greenhouse gas emission allowances requires the proof of the emitted amount of carbon dioxide (CO2) for many plants.

Usually the CO2 amount is measured by a rather complicated calculation method. The measurement of CO2 takes place directly in the exhaust duct, however the measurement of CO2 concentration in connection with the volume flow is also allowed. Independent of the fuel used and of other conditions, the determined CO2 value is available without manual analysis. The EU directive demands high criteria for direct measurement. For example, the total uncertainty of the mass flow value based on the CO2 and volume flow measurement has not to be larger than 2% ... 7%, depending on the size of the plant. SICK proves this to be possible.

Implementation

CO2 direct measurement fulfills the requested measurement accuracy

In a large power plant fired by brown coal, a test to prove the suitability of direct measurement was carried out. Four exhaust ducts were provided with GM35 gas analyzers and FLOWSIC100 flow devices and then they were geometrically measured with high precision. The concentration and speed profiles were determined by grid measurement with many measurement points. The calibration measurements at the four exhaust ducts showed that a total uncertainty of the CO2 mass flow calculation of

The comparison with thermo-dynamic reference analysis over a long period showed a very good correlation.

Customer benefits

In-situ is the solution

The cross duct version of GM35 in-situ analyzer measures the CO2 concentration via the complete duct diameter without changing the gas composition by sample conditioning. The FLOWSIC100 volume flow measurement device is also an in-situ device and measures integrally over the entire duct diameter. The measurement values of both devices result in the CO2 mass flow. For the realization, SICK relied on its experience with high-precision volume flow measurement with ultrasonic gas meters for custody transfer applications.

The vital advantages of the in-situ technology:

The in-situ solution requires no additional measurement of the exhaust gas humidity which - apart from reducing the effort - spares the tolerance of an additional, difficult measurement in consideration of uncertainty in practice.

As the exhaust is measured directly in-situ, uncertainties of sampling and treatment, which are vital for extractive measurement technology, become unnecessary.

Laborious sampling and the analysis of the fuel for the calculation method can either be reduced or omitted entirely.

The in-situ solution requires no additional measurement of the exhaust gas humidity which - apart from reducing the effort - spares the tolerance of an additional, difficult measurement in consideration of uncertainty in practice.

As the exhaust is measured directly in-situ, uncertainties of sampling and treatment, which are vital for extractive measurement technology, become unnecessary.

Laborious sampling and the analysis of the fuel for the calculation method can either be reduced or omitted entirely.